1. Field of the Invention
The present invention relates to a paper handling device in which a paper bundle piling one or more paper can be externally inserted.
2. Description of the Related Art
Recently, automation equipment, such as a cash dispenser (CD), an automated teller machine (ATM) and the like, are installed not only in financial institutes but also convenience stores and the like. A paper handling device is mounted on such automation equipment in order to handle bills as papers. In such a case, the paper handling device operates according to the instruction of the automation equipment.
The larger the number of pieces of bills is, the more troublesome it becomes for a customer to input bills one by one. Therefore, a bill bundle can be inputted to the automation equipment. Since sometimes only one piece of bill is inputted, the bill bundle means one piece of bill or more than two pieces of bills.
It cannot be expected for a customer to appropriately insert a bill bundle. For example, sometimes a customer inserts a bill bundle beyond allowance peculiar to automation equipment or a paper handling device. Therefore, some paper handling devices detect the height of an inserted bill bundle and return bill bundle whose height exceeds its height limit.
The height is conventionally detected by piling up a bill bundle horizontally or in a slope. However, since a piece of bill is light and has large elasticity compared with its weight, the total height of piled bills varies depending on their elasticity. Therefore, the height of a bill bundle cannot be always accurately detected. As a result, even when a bill bundle which number is below the limit of number to be handled is inserted, some bill bundles are often retuned to a customer.
Such a return requires a customer of labor more than needed. It also degrades the efficiency in use of automation equipment. For such a reason, it is important to measure the height of an externally inserted bill bundle more accurately.    Patent reference 1: Japanese Patent Application No. 2002-190051    Patent reference 2: Japanese Patent Application No. 2000-191216